The technology of the present disclosure relates to a fixing device and an image forming apparatus including the same.
Conventionally, there has been known a fixing device including an endless fixing belt heated by a heating unit, a pressing pad abutting an inner peripheral surface of the fixing belt, and a pressure roller brought into press-contact with the pressing pad at a predetermined pressure while interposing the fixing belt between the pressing pad and the pressure roller. The pressure roller forms a fixing nip portion between the fixing belt and the pressure roller and applies rotational driving force to the fixing belt.
In this type of fixing device, when the fixing belt slips with respect to the pressure roller, there is a problem that the fixing belt is locally heated by the heating unit and thus is broken. In order to avoid such a problem, there has been proposed a fixing device in which a cap member is mounted at an end portion of the fixing belt in a rotation shaft direction and rotation of the cap member is detected by a rotation detection unit, so that rotation of the fixing belt is indirectly detected. In this fixing device, only when the rotation of the cap member (that is, the fixing belt) has been detected by the rotation detection unit, the heating unit is operated. The cap member has a cylindrical part that covers an outer peripheral surface of an end portion of the fixing belt and a disc part that covers one end side of the cylindrical part.
A rotation transfer member including an elastic member has been bonded to an inner peripheral surface of the cylindrical part. The rotation transfer member make contact with the outer peripheral surface of the fixing belt and transfers the rotation of the fixing belt to the cylindrical part of the cap member. The rotation transfer member is compressively deformed at a contact portion with the fixing belt, thereby ensuring a contact pressure.